1. Field of the Invention
The invention relates to a dual casement window structure. More particularly, the invention relates to an aesthetic dual casement window structure with a good sheltering from rainwater and good ventilation.
2. Description of the Related Art
Referring to FIG. 1, a conventional casement window 1 is movably attached on three parallel rails 13a in a frame 1a. More specifically, a screen window 10a, an inner casement window 11a and an outer casement window 12a are movably attached on the rails 13a to slide along the rails 13a. However, during rainy days, rainwater easily penetrates the room through gaps between the components of the conventional casement window because there is not sheltering outside the casement window. If the casement window is closed to prevent rainwater penetration, an air conditioner has to be turned on to maintain a good ventilation of the room, which results in a wasteful energy consumption. Furthermore, the cooling medium used in the air conditioner is also consumed in a great amount, which detrimental to the environmental protection.
Referring to FIG. 2, a conventional pivotably casement window includes a frame 2a mounted on a wall, and a pivotably window leaf 20a mounted inside the frame 2a. During rainy days, the pivotably window leaf 20a is pushed outwardly to achieve a good ventilation and prevent rainwater penetration. However, in consideration of good ventilation, the performance of the pivotably window leaf is not as good as that of the casement window. Furthermore, the pivotably window leaf 20a is pivotally connected to the frame 2a, and therefore cannot be dismounted from the frame 2a for cleaning. The only way to clean the pivotably casement window for a user is therefore to stand as high as the pivotably casement window, which may be dangerous.
An additional canopy may be further mounted above the casement window to shelter from rainwater. However, the installation of the canopy is not handy, and shapes and colors of the canopy may not match with the perspective of the building. Therefore, there is a need of an aesthetic casement window with good rainwater sheltering and ventilation effects.